Crystalline Defects Induced during MPCVD Lateral Homoepitaxial Diamond Growth

Nanomaterials

Daniel Araujo¹  Fernando Lloret²  Etienne Bustarret³  David Eon³ 

[1] Dpto. Ciencia de los Materiales, Universidad de Cádiz, 11510 Puerto Real-Cádiz, Spain;Institute for Material Research, Hasselt University, 3590 Diepenbeek, Belgium;Univ. Grenoble Alpes, CNRS (Centre National de la Recherche Scientifique), Institut NEEL, F-38042 Grenoble, France;

关键词: diamond;    defects;    MPCVD;    TEM;    dislocations;    boron-doped diamond;    lateral growth;    selective growth;   

DOI  :  10.3390/nano8100814

来源: DOAJ

【 摘 要 】

The development of new power devices taking full advantage of the potential of diamond has prompted the design of innovative 3D structures. This implies the overgrowth towards various crystallographic orientations. To understand the consequences of such growth geometries on the defects generation, a Transmission Electron Microscopy (TEM) study of overgrown, mesa-patterned, homoepitaxial, microwave-plasma-enhanced, chemical vapor deposition (MPCVD) diamond is presented. Samples have been grown under quite different conditions of doping and methane concentration in order to identify and distinguish the factors involved in the defects generation. TEM is used to reveal threading dislocations and planar defects. Sources of dislocation generation have been evidenced: (i) doping level versus growth plane, and (ii) methane concentration. The first source of dislocations was shown to generate <110> Burgers vector dislocations above a critical boron concentration, while the second induces <112> type Burgers vector above a critical methane/hydrogen molar ratio. The latter is attributed to partial dislocations whose origin is related to the dissociation of perfect ones by a Shockley process. This dissociation generated stacking faults that likely resulted in penetration twins, which were also observed on these samples. Lateral growth performed at low methane and boron content did not exhibit any dislocation.

【 授权许可】

Unknown